I was about to post that same thing - big drops in NET, Kenpom, Bart Torvik (who's model really hates us) and BPI.
To me, thats the frustrating thing about all those predictive metrics, they can swing wildly even this late in the season when you play poorly and get the doors blown off, even on the road. It rewards and punishes a style of play and late game strategies, encouraging teams to either keep the foot on the gas even when there is no doubt, or try to scramble and make the score "more respectable" late even though you have no chance.
Had the game been 64-54 or 70-61 instead of 70-54 due to a couple late baskets (or missed baskets), the numbers don't change nearly as much, but was the game any less or an a$$ kicking? No.
I just have a hard time understanding the math as to how this late in the season (with all the data already accrued), one game can swing numbers so much.